Electric insulation.



J. A. HEANY.

ELECTRIC INSULATION.

APPLICATION FILED SEPT. 23. I914.

Patented 001;. 5, 1915.

JOHN ALLEN HEANY, OF NEW YORK, N. Y.

ELECTRIC INSULATION.

Specification of Letters Patent.

Patented Oct. 5, 1915.

Application filed September 23, 1914. Serial No.863,1 24.

To all whom it may concern.

Be it known that I, JOHN ALLEN HEANY, a citizen of the United States, residing in the city, county, and State of New York, have invented certain new and useful Improvements in Electric Insulation; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to a new and useful insulating medium for electric conductors comprising a foundation thread or filamentary body associated with a flattened layer or sheath of matted fibers of asbestos, cotton, jute, hemp or the like associated therewith, and preferably provided with a suitable cement or binding agent, the whole constituting a continuous tape or band of substantially homogeneous and uniform structure adapted to be wound about or superposed upon the conductor to be insulated to produce a highly efiicient insulating covering which may also be fire-proof and water-proof and which may be made quite thin without impairing the high resistance factor of the finished insulator.

In my prior Patent, No. 1,071,676, dated Aug. 26, 1913, I have described and claimed a novel method of insulating conductors by applying to the surface thereof a covering of fiber-coated thread, and the present invention involves a modification of the fibercoated thread described in the patent aforesaid designed to produce the fibrous insulation associated with the supporting or foundation thread thereof in the form of a thin tape or ribbon of any desired width well adapted to be wound upon or otherwise applied to the conductor to efficient insulating sheath.

In the accompanying drawings, Figure l is a diagrammatic representation of means for producing the insulating tape in the form of fibers matted about a thread or the like and impregnated with a suitable binding or coating agent. Fig, 2 is an enlarged fragmentary view of a section of tape showing the relation of the foundation cord or filament and the fibers matted thereon. Fig. 3 illustrates the mode of applying the tape to an electric conductor.

In my former patent hereinbefore identifie I have discussed the method and appro priate apparatus for producing fiber-coated provide a highly threads or filaments constituting the preliminary product from which the ultimate insulating sheath for electric conductors and the like is produced, and in carrying out the present invention, it is proposed to produce the same character of preliminary fibercoated thread or filament, in the manner and according to the successive operations set forth in the patent aforesaid, and reference is made to said patent for the detailed description of the mode and means for preparing the thread with a substantially uniform coating of fibers twisted and matted thereon, and the fiber-coated thread thenwound upon suitable spools or bobbinsfor subsequent use.

In the prior patent aforesaid, the fibercoated thread was applied, in conjunction with an impregnating agent, to the surface of the conductor, and the sheath of insulating material produced by the. successive convolutions of fiber-coated thread was worked down and smoothed to form a layer of substantially uniform thickness. According to the present invention, however, the preliminary fiber-coated thread is to be treated soas to reduce the same to the form of a tape or ribbon by flattening the body of matted fibers surrounding the foundation thread, thereby reducing the body of fibers to a relatively thin layer having considerable width to produce the tape or ribbonlike form, inwhich the disposition of the fibers is practically uniform and homogeneous and in a measure resembling a continuous thin strip of felt.

Referring to Fig. 1 of the drawings, 1 indicates a spool, bobbin or reel having wound thereon a cord or filamentary body having its surface coated with a layer of twisted and matted fibers, applied in the particular manner described in my patent aforesaid. In this connection, it will be noted that the fibrous coating of the thread is twisted and matted rather loosely but uniformly about the foundation thread, and may, if desired, be held in proper relation on the thread foundation'by any suitable binding agent as described in the patent aforesaid. From the storage reel or spool 1, the fiber-coated thread is led through flattening rollers 12 and 13, and just prior to the passage of the thread through the rollers aforesaid, there is applied an impregnating agent which may be either in the form of an adhesive, a water-proofing, or a fire-proofing agent, or any preferred combination of such agents. of applying said impregnating agent to the fiber-coated thread consists in passing the latter through a. tank or receptacle 9 containing the impregnating agent 8, prefer-- ably in liquid form, the thread being guided through the tank by means of a suitable roller 10. As the fiber-coated thread passes through the rollers 12 and 13-the impregnating agent is worked into the body of the fibrous coating, and the latter is flattened out into a thin tape or ribbon-like body of uniform thickness with the fibrous coating inclosing and surrounding the foundation thread, as illustrated in Fig. 2. As the fiattened tape-like fiber-coated thread leaves the rollers 12 and 13, it is passed through a drying device, which may be conveniently made in the form of an electric heating coil 15 connected to current leads 16 and 17, after which it is taken up by rewinding spool or reel 6, from which it may be unwound to be applied to the conductor to be insulated.

As indicated in Fig. .2, the insulating medium consists of the foundation thread or filament 2' embedded in a thin, flat and relatively wide sheath or covering of matted and twisted fibers constituting a. substantially smooth, uniform, tape-like or ribbonlike body which may be wound directly upon the conductor to be insulated or otherwlse applied to the surface thereof to produce an even and uniform'insulating sheath for the conductor, in the manner shown in Fig. 3, which sheath may, if desired, be further treated with any suitable medium to render the same impervious to moisture or A convenient mode fire-proof if desired. As indicated in Fig. 3 the tape or ribbon-like insulating medium is laid up on the conductor'm in successive convolutions, and if desired successive layers of the tape may be superposed and bound together by a suitable adhesive or other impregnating agent, applied to the insulating tape either before or after it is Wound upon the wire, the sheath or coating about the wire then being calendered or otherwise treated, if desired, to render the same absolutely smooth, uniform and homogeneous.

It will be apparent that many other forms of apparatus may be employed for producing the novel form of insulating material described, and that the particular forms of apparatus illustrated are merely exemplary.

What I claim is 1. An insulating medium for electric conductors comprising a tape or ribbon having a foundation cord or filament and an inclosing flat sheath of matted fibers.

2. An insulating medium for electric conductors comprising a foundation cord or filament associated with an inclosing flattened layer of matted fibers and a binding agent.

3. An insulating medium for electric conductors comprising a tape or ribbon having a foundation cord or filament and an inclosing fiat sheath of matted asbestos fibers.

In testimony whereof I aflix my signature, in presence of two witnesses.

GEORGE D. DAVIS, VIOLA B. SMITH. 

